1. Field of the Invention
The present invention relates to an apparatus for drilling holes in a material and, more particularly, to an apparatus for drilling precisely positioned hinge screw pilot holes in cabinet doors.
2. Description of the Prior Art
Because cabinet doors are constructed of relatively hard wood, it is necessary to drill pilot holes for the hinge screws. These pilot holes serve two purposes: they assure proper positioning of the screws on the cabinet door and they facilitate engaging the screws in the face of the door. The screw pilot holes must be properly positioned with respect to each other and offset a precise distance from the edge of the cabinet door. If the pilot holes are not exactly located, the cabinet door will be misaligned with respect to the frame upon which it is mounted.
The classic method of making pilot holes in a cabinet door is quite primitive. A cabinet maker places a hinge on the back of a cabinet door and visually aligns it. He then marks the approximate center of each hinge aperture, removes the hinge, and, with a hand-held drill, drills pilot holes into the wood. Due to the inherent inaccuracies of this method, the cabinet maker cannot merely insert the hinged screws and tighten them down. On the contrary, the cabinet maker must make numerous small adjustments as he tightens the hinge screws to insure that the cabinet door is in proper alignment with the cabinet frame.
A second prior art solution to the problems encountered in mounting hinges on cabinet doors is an automatic hinging machine. This very sophisticated device automatically positions both the upper and lower hinges on a cabinet door, drills both groups of pilot holes, and simultaneously inserts and tightens all hinge screws. This device is very complex and quite expensive.
A primary drawback of this device, other than its very high cost of acquisition, is that time consuming disassembly and modification is required to adapt it for use with cabinet doors of differing lengths. If, for instance, the automatic hinging machine has been mounting hinges on a relatively short cabinet door, its mounting machinery must be located relatively close together. If the user of this machine then desires to mount hinges on larger cabinet doors, the automatic hinging machine must be substantially dismantled so that the drilling and screwing mechanisms can be repositioned at a location further apart from each other. This is a very time consuming process which users normally avoid by scheduling only very long production runs for each size cabinet door.
The primary disadvantage of manually mounting hinges on cabinet doors is that it requires a highly skilled cabinet maker and is a time consuming procedure. The primary disadvantage of the automatic hinging machine is that it is very costly and cannot be quickly adapted to handle cabinet doors of varying sizes.